A nasty virs "Autorun.inf"

I got a virus from a visitor's USB drive. It messes up direct access to the hard drive, Open and Explore is replaced by garbled text in turn I can not double click to open the HD contents. I could use Keybord short cut to access the contents, however. What is most annoying that it copies itself onto any write able media.
Norton does not even detect it, I could only delete it using McAfee enterprise version.
I have tried system restore, first boot after the system restore is good but sometimes later same thing, I have scanned the system in safe mode, no luck!
Help!!!